Young extends advantage at halfway mark in Miami

His lone blemish was a bogey at the par-4 14th, but he got the stroke back two holes later when he drove the green at the par-4 16th and coolly two-putted for his 14th birdie of the week.

"There's a lot of golf to be played on a difficult golf course," Young said.

"But so far, I've played well."

Young played with world No.1 Scottie Scheffler, who's bogey-free 67 left him exactly where he started the day — seven shots off the lead.

Nick Taylor (70), Alex Smalley (71) and Jordan Spieth (71) were tied for second. Gary Woodland (69) was alone in fifth at seven under and Scheffler was in a logjam of players — Alex Fitzpatrick (66) among them — at six under.

"I definitely need to not get further away," Scheffler said.

"All I can do is go out there and be committed to what I need to do and that's pretty much it."

Spieth rolled in a birdie at the par-4 last, an absolute rarity through the first two rounds. It was only the sixth on the 18th through the tournament's first two days on the Blue Monster course.

Young's second shot at the finishing hole bounced off the base of the bleachers, coming to rest in the middle of a nest of cables on the ground well behind the green. He took a drop, didn't get a great lie of out that, and still chipped to tap-in range to save his par.

Kurt Kitayama and Sudarshan Yellamaraju — the first group off the tee — took full advantage of calm conditions, soaring up the leaderboard to four under for the week. Kitayama (64) had the round of the day and Yellamaraju dropped three shots on his final two holes to finish with a 66.

"The rhythm, being first off, helps. We didn't have to wait for anyone, kind of going at our own pace, not worrying about being behind or waiting on a group," Kitayama said.

"And so, when you're both playing well, it's nice to feed off each other's energy."

Min Woo Lee had an even-par 72 to sit two under as the best-placed Australian, while compatriots Jason Day (70) and Adam Scott (71) are three over.